The Wireless Intelligent Network (WIN) architecture defines a model for the current cellular wireless and PC S networks. The concept of intelligent telephony networks was first implemented in wireline networks. Under the model of Advanced Intelligent Network (AN), wireline networks provide centralized control of telephone services to subscribers through diversely located central office switching systems. In an AIN system, central offices send and receive data messages from a SCP via a STP.
AIN-like networks provide personalized services to individual subscribers. It is important to note that any services provided to individuals while they are roaming or away from a home location require the subscriber to manually notify the network of his present location. The AIN model does not provide for mobility management that is based in the network.
Prior art AIN systems are exclusively land line communications systems, which provide telephone communication services via wired telephone lines. The signaling protocol used for AIN allows only for control of telephone network switching elements in response to processes or software functions that are based on the calling number, called number and other relatively fixed items, such as time of day, congestion control and end user control. Wireline communications, even those provided by the AIN, are necessarily limited by the fixed nature of installed lines. These systems make no provision for communications with any mobile link, except as taught by Emery et al. in U.S. Pat. Nos. 5,469,496 and 5,506,887.
While AIN provides the intelligent processing related to the wireline networks, WIN is the intelligent processing for wireless networks. In many ways they are similar and have used similar technologies, however, the model for WIN provides for the additional element of mobility. In the AIN architecture, both the originating and terminating telephones are assumed to be fixed, while in the WIN architecture the location of mobile subscribers must be tracked by the networks. The HLR is the data register that tracks the location of the mobile. The HLR contains profiles for each subscriber.
The wireless telecommunications industry has developed roaming standards which allow automatic handoffs from one cell to another during an established call, and to allow customers to roam from one system or network to another while having incoming calls follow the customer to the visited system. The protocol that accomplishes this functionality is set out in the EIA/TIA standard IS-41. The IS-41 protocol is an out-of-band signaling protocol, which may be transported by either X.25 or SS7 links.
The air interface link between the mobile cellular user and the appropriate base station uses particular radio frequencies that have been mandated by appropriate regulatory bodies. Dedicated trunk lines serve as the link between the base station and the MSC, and the interface between MSCs within the same system (same cellular carrier) is generally provided by dedicated land lines. Data links connect the mobile switching center to a VLR and HLR which can be located at the mobile switching center or at a remote point. The HLR may serve more than one MSC, but the VLR is typically dedicated to a particular MSC. The HLR is the location register that contains information about the user, such as directory number, profile information, feature list, current location, serial number, services authorized and validation period. The VLR is the location register on which an MSC temporarily stores information regarding a visiting subscriber or user. The difference between the VLR and the HLR is simply that the HLR is the permanent storage place for the subscriber record while the VLR is a temporary storage place used during a configurable time. The use of the VLR reduces the amount of network signaling needed to process the call handling. The subscriber record on the VLR is erased when the mobile is no longer active or has moved to another MSC.
Many mobility controllers of the above described cellular systems are now programmed to provide subscribers with selected special services. If the mobile subscriber had roamed to another system and registered on that system, the special features did not necessarily follow the subscriber. To enable seamless roaming for subscribers who use special services, the Wireless Intelligent Network (WIN) was developed. The WIN was developed as an extension to the CTIA's reference model. The first capability centers around consolidation of the network's location functions. Secondly, the network must have a robust SCP platform that runs multiple applications, and thirdly, the network must be enhanced by new "primitive" capabilities. A key enhancement to the WIN was realized by adding Service Control Function (SCF) functionality to the reference model. The SCF function replaced the HLR in the model and the HLR was redefined as an application using the SCF.
The WIN comprises three unique components. A MSC switch that provides call processing, including inherent service switching point (SSP) capabilities and features such as call waiting, call forwarding, and three-way calling. Second, the system uses the EIAITIA IS-41 SS7 TCAP message protocol to provide intersystem handoff, automatic call delivery, automatic roaming and most importantly, remote feature access. Third, the WIN SCP provides mobility management, and a platform for hosting service logic for network applications.
Traditionally, the architecture of wireless networks places the burden of hosting new service applications on the mobile switch (MSC). MSCs are an expensive network element and are typically limited in the computing and database capacity needed to host new services. Therefore, MSCs are not well suited to support growth. By adopting the WIN architecture, wireless carriers place more network intelligence and mobility management functionality into SCPs. The WIN architecture is currently under deployment by various cellular carriers and is suited for use in all cellular and PCS networks.
Currently, consumers generally have access to wireless networks that offer voice service. In a few cases, carriers who use the WIN architecture and certain PCS carriers offer minimal advanced services such as short messaging or voice mail. The primary reason that consumers have such a limited suite of services from which to choose is due to the time and expense of developing services for use on a network wide basis. These services take many months to develop and must be justified by a business case that assumes use by the general population. The subject invention enables new applications to be developed and hosted in a focused, inexpensive and timely fashion to respond to customer demands.
Three issues must be addressed to meet the challenge of profitable, highly functional wireless networks. First, wireless applications must have a platform for operation that allows custom application tailoring to an individual customer's need, rather than the overall needs of all network users. Second, if this type of customization is to happen, the cost basis and development paradigm for these wireless applications must change dramatically. Third, billing and provisioning systems must be adapted to allow carriers to manage a new level of service flexibility and customization.
In prior art systems if a subscriber is unable to receive calls on a wireless device, or if the subscriber is not active on the wireless device, but wishes to have the calls sent to a specific device only if the subscriber is available at that new device, the subscriber must manually set the call-forward-immediate feature of the wireless device to have calls forwarded to another device, such as an office telephone. Therefore, if the subscriber desires to receive all incoming calls on the telephone in his or her office, then he or she must manually set the call-forward feature of the wireless device in order to receive calls that are directed to the wireless device. If the subscriber forgets to get the call forward feature, then calls to the wireless device will not be forwarded. Moreover, in prior art systems once the call forward feature is set, all calls to the wireless device continue to be forwarded to the wireline telephone even if the subscriber has left the office. Thus, once the user becomes inactive on the wireline phone and wants to receive calls on the wireless system again, he has to manually disable the wireless device's call forward feature.
Moreover, prior art systems do not provide call screening for calls forwarded from the wireless phone to the office wireline extension. Thus, all calls made to the wireless phone are forwarded to the wireline phone when the call-forward feature of the wireless phone has been manually set. This may not be a desirable arrangement if the subscriber does not want to be interrupted in the office by calls from a preselected group or at certain times of the day.
Prior art systems also do not provide for the interconnection of data applications executing in private networks with WIN signaling and control networks to make data applications WIN aware.
It is an object of this invention to provide an improved combined network system consisting of both a wireline network and a wireless network wherein the wireline network appears as a node on said wireless network and allows open architecture applications on said private network to run on said wireless network.
It is a further object of this invention to provide a system whereby wireline telephones may be treated by a mobile network management system as if they were mobile telephones assigned to the wireless network.
It is yet another object of this invention to provide a method of connecting wireline or private network-based applications to network based applications in both AIN and WIN models.
A further object of the invention is to reduce the cost of running specialized applications on wireless networks by utilizing portions of a private wireline network in lieu of multiple service control points.
A further object of the present invention is to provide an automatic call redirection system between a wireless and a wireline network.
A further object of the present invention is to detect when a user is active on a wireline telephone and to automatically forward calls from a wireless phone to a wireline telephone when the user is active on the wireline phone.
Another object of the present invention is to detect when a user becomes inactive on a wireline telephone and to automatically forward calls from the wireline telephone to a wireless telephone.
A further object of the present invention is to provide call screening for calls forwarded between wireline and wireless networks.